1. Field of the Invention
This invention relates to a method of aggregation of a two-level packet for hybrid topology wireless sensor network, which belongs to a wireless communication technology.
2. Description of the Related Art
Since 21st century, with the rapid development of disciplines, such as MEMS (Micro-Electro-Mechanism System), computer, communication, and automation control and artificial intelligence, a new type of control networks—WSN (Wireless Sensor Network) comes into being.
WSN is an intelligent and autonomous monitoring and control network system, which consists of many ubiquitous tiny sensor nodes having communication and computing capabilities. These sensor nodes are densely planted in an unattended monitoring area and complete the assigned task according to the environment. WSN is a large scale, unattended, resource-limited distributed system and utilizes multi-hop peer communication, the network topology of which dynamically changes with self-organizing, autonomous, adaptive and other smart properties. If the Internet has changed the communication way among people, the WSN would merge the logical information world and the real physical world together, which will change the interaction way between people and nature. The emergence of WSNs has attracted worldwide attention.
However, energy consumption is a major problem of WSN. Packet aggregation, which can reduce the header overhead and the number of packets, becomes an effective energy-saving method. WSN for industrial monitoring and other applications requires the battery-powered nodes and the network lifetime must last 2 to 3 years. Therefore, the energy problem is more prominent. In addition, these applications have periodic characteristics and usually use hierarchical network topology. These networks are configurable and suitable for packet aggregation. Until now, there have been no two-level packet aggregation methods for such WSN applications.